A spam engineer at Microsoft has warned that hackers can use Android powered tablets and smartphones to send spam emails. Android users should be cautious to install any mobile apps that do not come from the Google Play Store or the Amazon Appstore since a new malware app has been reportedly sending spam emails through affected devices. Terry Zink says that a new app is sending out emails with the signature “Sent from Yahoo Mail on Android” and the messages are starting to come from a number of locations including Indonesia, Chile, Lebanon, Oman, Philippines, Russia, Saudi Arabia, Ukraine and Thailand.

Zink wrote on an MSDN blog, “I’ve written in the past that Android has the most malware compared to other smartphone platforms, but your odds of downloading and installing a malicious Android app is pretty low if you get it from the Android Marketplace, but if you get it from some guy in a back alley on the Internet, the odds go way up.” The malware affected app logs into your Yahoo account through your Android device and then starts by sending out spam messages.

The app does not seem to be coming from Google’s Play Store, so that is a little less to worry about, but users who attempt to download hacked, pirated or other versions of official apps should be aware they could contain the malware code. Malware type apps have appeared in the past and sent spam text messages from users phones in order to rack up phone bills to unsuspecting smartphone users. The “botnet” virus gives the hacker just enough access to your account to send the spam messages. The messages have not been sent anywhere in the United States yet, but that does not mean you are 100 percent safe either.

Users can avoid malicious content from mobile app download stores if they stick to official stores like the Amazon Appstore and Google Play Store which scan for potentially harmful mobile apps and remove them from the store or deny their submission altogether. If you are concerned about downloading the wrong type of mobile app you can follow a couple easy steps. Before the app is installed on your device, the Android software will show you what permissions it has on your phone. If you are downloading a game app, you might want to make sure it does not have access to your contact list. You can get more tips for downloading safe apps online.